The present invention relates to handcuffs for locking about the wrists of individuals and more particularly relates to a handcuff having improved protection against picking the lock of the handcuff.
The present invention constitutes an improvement to the handcuffs disclosed in U.S. Pat. No. 4,287,731 issued of common assignee herewith. In that patent, the handcuffs include a generally arcuate jaw having ratchet teeth at one end and pivotally coonnected at its opposite end between a pair of spaced cheeks. The cheeks are enlarged at their opposite ends and a lock assembly is enclosed therebetween. Briefly, the lock assembly includes a bolt having ratchet teeth along one side and pivoted at one end between a locked position engaging the ratchet teeth of the jaw and an unlocked position with the ratchet teeth spaced from the ratchet teeth of the jaw. A spring biases the bolt into its locked position and is also slidable into a bolt detenting position to double lock the bolt. In using these handcuffs, a key with a lateral projection at one end is inserted into a key opening in one of the cheeks. Upon rotation of the key in one direction, it slides the spring from its double locking position. Upon rotation of the key in the opposite direction, the key lifts the bolt from locking engagement with the jaw.
While the above described handcuffs have proven satisfactory, it is still possible for the lock to be picked. For example, in practice the double lock may not be utilized leaving only the bolt under the bias of the spring in locking engagement with the jaw. It is possible to insert a pin having a lateral projection on its end, or a bent paperclip, into the keyhole to engage the locking shoulder on the bolt and lift the bolt from its locking position. Even when double locked, an individual knowledgeable in the construction and operation of the handcuff lock may be able to first slide the spring from its double locking position and thereafter lift the bolt from its locked position. Accordingly, there has arisen a need to provide in a handcuff of this type additional protection against picking the handcuff lock.